Shrieker

Hello, it is from "the Exploits of Engelbrecht" - a British surrealist novel written in the 40s/50s by Maurice Richardson.
It is election time and here is the political picture :
"In the middle of his maiden speech, shorty after the liquidation of parliament, the last holder of the seat refused to accept the Shrieker's directive to pipe down."

I am not familiar with British rural constituencies and assemblies, and I guess "shrieker" must be an invention of the author, but what's the name of the person usually in charge of good behaviour during sessions ?
Thanks.

The shrieker is an invention. A chairman would usually be in charge of good behaviour during sessions.

However, various societies, the Freemasons, The Water Buffalos, The Oddfellows, etc., all have grandiloquent titles for officials whose duties are mainly ceremonial; Maurice Richardson has adapted this quirky naming system for his own purposes with "Shrieker" which is, at least, half-believable.